Rivet gun



Oct. 25, 1966 D. H. MOLITOR ET AL 3,280,615

RIVET GUN 2 Sheets-Sheet 1 Filed May 25, 1964 INVENTORJ N WWW R. E N M T C 0 m T F A ML 1 fimm 0 W Oct. 25, 1966 MOLITOR ET AL 3,280,615

RI VET GUN 2 Sheets-Sheet 2 Filed May 25, 1964 I VVENTORJ NR W wm E 0 2 m A0 0 HM. r M m .D 7% A 1 mg 0 w,

United States Patent 3,280,615 RIVET GUN Donald H. Molitor, Farmington, and Russell F. Richardson, St. Paul, Minn., assignors to The Richline Co., Inc., St. Paul, Minn., a corporation of Minnesota Filed May 25, 1964, Ser. No. 369,982 7 Claims. (Cl. 72-391) This invention relates to a hand tool for setting rivets. It relates to a rivet gun of the type in which the rivet may be set blind, that is, the rivet is inserted into the work and secured therein from the same side without need for access to both sides of the work. More particularly, this invention relates to a hand-operated rivet gun designed for used in cramped and relatively inaccessible locations.

The invention is illustrated in the accompanying drawings, in which the same numerals are used to identify corresponding parts and in which:

FIGURE 1 is a side elevation showing the tool as used to set rivets in tight, cramped locations which are inaccessible to most rivet guns;

FIGURE 2 is a fragmentary elevation on an enlarged scale and in section showing the working parts of the rivet gun with a rivet inserted into a work piece before application of force to set the rivet therein;

FIGURE 3 is a similar enlarged fragmentary elevation in section showing the rivet expanded and the head of the rivet supporting mandrel about to be snapped off;

FIGURE 4 is a similar enlarged fragmentary elevation in section showing the parts in position just after the rivet supporting mandrel has been separated from its head to free the rivet gun from the set rivet and the work piece;

FIGURE 5 is a transverse section on the line 5-5 of FIGURE 4 and in the direction of the arrows; and

FIGURE 6 is a fragmentary elevation in section on the line 6-6 of FIGURE 3 and in the direction of the arrows.

Referring to the drawings, the rivet gun according to the present invention includes a generally hollow frame, indicated generally at 10, having an elongated palm engaging handle portion 11 having an interior groove or channel 12 into which a trigger-like finger engaging handle 14 is adapted to be fit along a portion of its length.

The frame includes a head portion 15 extending generally transversely relative to the direction of the handle portion and having a longitudinal bore 16 extending through it. Bore 16 communicates with channel 12. It is provided with an opening 17 at one end for the ejection of spent mandrels and is threaded along a portion of its length 18 to receive a threaded chuck 19. Chuck 19 forms an extension of the head portion of the frame. The outermost end of chuck 19 is tapered. Chuck 19 is hollow having a central cylindrical bore 20 and a central muzzle bore 21 of lesser diameter connected together by an interior tapered wall 22.

An elongated sleeve member, indicated generally at 23, is positioned Within chuck 19 for relative longitudinal movement. Sleeve 23 is provided with a relatively short head portion 24 which is of a larger diameter to fit with a slide fit within bore 20 of the chuck and relatively elongated stem portion 25 of lesser diameter adapted to fit With a slide fit Within the muzzle bore 21 of the chuck. The stem portion 25 of the sleeve is provided with a transverse slot 26 which extends through the stem portion of the sleeve for a portion of its length adjacent to but spaced inwardly from the muzzle end of the sleeve.

The sleeve is provided with a longitudinal bore 27. The muzzle end of bore 27 is enlarged and threaded at 28 to receive a threaded bushing 29. Bushing 29 functions as a nozzle and as an adaptor to receive mandrels of different sizes from rivets of different sizes. That is, bushings of different sizes are readily interchangeable with the chuck in order to adapt the rivet gun to the setting of rivets of various sizes.

A pair of toothed jaw members 30 are positioned partially within the transverse slot 26 in the stem portion 25 of sleeve 23. Each of the jaw members 30 is provided with an outer flanged edge 31 extending into the longitudinal bore of the chuck opposite from and generally parallel to the toothed edge. This flange functions to restrict the movement of the jaws inwardly and insure their proper alignment at all times. Each jaw member also has an inclined edge portion extending away from the flanged edge and adapted to engage the inside tapered surface 22 of the chuck 19.

In the assembled rivet gun the inclined edges of the jaw members 30 are maintained in contact with the tapered surfaces 22 by means of a compression spring 34. This spring extends around the stern portion 25 of sleeve 23 and is seated against the enlarged head 24 of the sleeve and against a washer 35 extending around the stern of the sleeve to exert the force of the spring against the jaw members.

The opposite end of sleeve 23 is restrained for limited movement by means of the finger engageable handle portion 14. Handle portion 14 is pivoted for limited movement relative to frame 10 by virtue of pin 36 which extends through the walls of the frame and finger engageable handle portion. In its relaxed position, as shown in FIGURE 2, handle portion 14 is urged against a stop 37 in the frame by means of spring 38. With the handle portion 14 in this position the sleeve 23 is in its innermost position in the frame, being urged by spring 34. The enclosed end of handle portion 14 within the frame beyond the pivot pin 36 and opposite from the exposed elongated finger engaging end is bifurcated. These spaced apart bifurcated end members 39 have arcuate edges and function as a cam acting upon the end of sleeve 23.

The innermost end of the enlarged head portion of sleeve 23 is cut away on opposite sides to provide a pair of spaced apart end shoulders 40 between a projecting spacer portion 41. The projection 41 fits between the handle cam portions 39 and the arcuate cam edges of the cam portions 39 of the handle bear against shoulders 40. Thus, when the finger engageable handle portion 14 is squeezed it rotates on pin 36 and its cam portions 39 bearing against shoulders 40 of sleeve 23 push the sleeve forward through the chuck 19 against the pressure of spring 34.

In the operation of the device, the gun is first loaded by inserting the mandrel 45 of a rivet through the nozzle bushing 29. The rivets set with the gun of this invention are of the type having a hollow tubular shank or body 46 which extends through the work W to be riveted and having an annular head 47, which may be flat or domed or countersunk. The mandrel 45 is inserted through the rivet in the reverse direction, that is, with the head 48 of the mandrel at the opposite end from the head 47 of the rivet. The mandrel 45 is inserted through the bushing 29 until the head of the rivet butts against the end of the bushing. The body 46 of the rivet is inserted through an appropriately sized hole in the work W to be rivted together. The gun and rivet are then in the positions shown in FIGURE 2.

While holding the gun in place the operator then squeezes the finger engageable handle portion 14 against the pressure of spring 38. This pushes the sleeve 23 forwardly through the bore of the chuck 19 against the pressure of spring 34. Because the assembly comprised of sleeve 23, jaws 31, spring 34 and washer 35 are seated in the bore of the chuck with the inclined surfaces of the jaws 30 hearing against the tapered wall surfaces 22 on the inside of the chuck, the forward movement of the sleeve assembly causes the jaws to move inward toward one another in the slot 26 and tightly grip the mandrel 45.

i the rivet mandrel is thus tightened. As the bushing 29 advances with the sleeve relative to the jaws the force of the end of the bushing against the fact 47 of the rivet pulls the rivet mandrel through thetubular shank 46 of the rivet. This action causes the head 48 of the mandrel to spread apart the portion of the tubular shank 46 of the rivet which extends through the opposite side of the work piece. This is shown in FIGURE 3.

Then, as the handle is squeezed further and the sleeve assembly is moved further through the chuck exerting greater longitudinal force on the rivet mandrel 45, the head 48 of the mandrel becomes more firmly seated in the spread apart tubular shank of the rivet and the rivet mandrel is snapped free from its head. This then releases the gun from the rivet, which is now firmly set in the work piece.

The spent mandrel is easily ejected through the longitudinal bore 27 of the sleeve 23 and opening 17 in the frame by releasing the handle to relax the spring tension on the jaws to permit the mandrel to be freed from the jaws. As the sleeve member retracts into the chuck, the outermost end of slot 26 nudges the ends of the jaw members to cause them to relax their bite into the mandrel to release it. The entire operation as described, from loading of the gun, setting the rivet and discharge of the spent mandrel takes only a matter of seconds and the tool is ready for reloading.

The rivet gun according to the present invention is compact and durable. It is light weight and has a small operating head for easy access to hard-to-get-at areas. It is easily operated with one hand only leaving the other hand free. It is easily assembled and maintained for trouble-free operation. It is easily operated over long periods without fatigue. It is useful for setting rivets in a wide variety of applications such as in sheet metal assembly, duct work, attachment of body panels, window channels, sign work, assembly of a great many different parts of all kinds, and the like. It is adapted to setting rivets of a variety of sizes and materials, such as aluminum rivets with aluminum mandrels, aluminum rivets with steel mandrels and steel rivets with steel mandrels, and the like.

It is apparent that many modifications and variations of this invention as hereinbefore set forth may be made without departing from the spirit and scope thereof. The specific embodiments described are given by way of example only and the invention is limited only by the terms of the appended claims.

We claim:

1. A rivet gun of the class described comprising a frame having a stationary palm engaging handle portion, a finger engaging handle portion pivotally attached to said frame, said gun having a relatively short head portion, a longitudinal bore extending through said head port-ion and having a restriction adjacent the muzzle end thereof, a sleeve assembly disposed within said bore for limited movement therein, a longitudinal bore extending through said sleeve assembly at least one transverse slot intersecting said longitudinal bore in said sleeve assembly, at least two toothed jaw members in said transverse slot, said jaw members being moveable in said slot into the path of the longitudinal bore through the sleeve assembly upon engagement of the jaw members with the restriction of the longitudinal bore through the head portion of the gun upon movement of the sleeve assembly therein upon movement of said finger engaging handle portion, said jaw members being each provided with an external flange along the edge opposite from its toothed portion, said flange being wider than said transverse slot 4 and effective to control inward movement of said jaw members and maintain alignment of the'jaw members in said slot.

2. A rivet gun of the class described comprising:

(A) a frame having an elongated stationary palm engaging handle portion;

(B) an elongated finger engaging handle portion pivotally attached to said frame and moveable relative to said palm engaging handle portion;

(C) said gun having a relatively short head portion at one end of said frame and extending generally transverse to the direction of the handle portions,

(D) a longitudinal bore extending through said head portion and having a tapered restriction adjacent the muzzle end thereof,

(E) a sleeve assembly disposed within said bore for limited movement therein in response to movement of the moveable handle portion;

(F) a longitudinal bore extending through said sleeve assembly,

(G) at least one transverse slot intersecting said longitudinal bore in said sleeve assembly,

(H) at least two toothed jaw members in said transverse slot,

(I) said jaw members extending outwardly from said slot into the longitudinal bore through the head portion of the gun,

(I) said jaw members being moveable in said slot inwardly into the path of the longitudinal bore through the sleeve assembly upon engagement of the extending portions of the jaw members with the tapered restriction of the longitudinal bore through the head portion of the gun upon movement of the sleeve assembly therein,

(K) said jawmembers being each provided with an external flange along the edge opposite from its toothed portion, said flange being wider than said transverse slot and effective to control inward movement of said jaw members and maintain alignment of the jaw members in said slot.

3. A rivet gun according to claim 2 further characterized in that finger engaging handle portion is pivoted in said frame adjacent one end of the handle portion, the relatively longer part thereof extends from the frame being exposed and moveable toward the stationary palm engaging handle portion, and the relatively shorter part thereof engages said sleeve assembly to move the sleeve assembly upon movement of the moveable handle portion.

4. A rivet gun according to claim 3 further characterized in that the relatively shorter part of said moveable handle portion is provided with an arcuate cam edge and one end of said sleeve assembly is engaged by said cam edge for movement by cam action.

5. A rivet gun according to claim 3 further characterized in that said engagement between the sleeve assembly and relatively shorter part of the moveable handle portion is maintained by means of a compression spring disposed around the sleeve assembly within the longitudinal bore extending through the head portion to exert force against the restriction at the muzzle end of that bore.

6. A rivet gun according to claim 5 further characterized in that said compression spring is disposed to exert force against those portions of the jaw members extending outwardly from the transverse slot to maintain the jaw members in engagement with the tapered restriction of the longitudinal bore through the head portion.

7. A rivet gun of the class described comprising:

(A) a frame having an elongated stationary palm en-- portion; the relatively longer part thereof extending from the frame and being movable toward the statronary palm engaging handle portion, the relatively shorter part thereof being moveable in the opposite direction,

(C) said gun having a relatively short head portion at one end of said frame and extending generally transverse to the direction of the handle portions,

(D) a first longitudinal bore extending through said head portion and having a tapered restriction adjacent the muzzle end thereof,

(E) a sleeve assembly disposed within said first bore for limited longitudinal sliding movement therein in response to movement of the moveable handle portion,

(F) the relatively shorter part of said moveable handle portion being provided with an arcuate cam edge and one end of said sleeve assembly being engaged by said cam edge for movement of said sleeve as sembly by cam action,

(G) a compression spring disposed around said sleeve assembly within said first longitudinal bore to maintain engagement between the end of said sleeve assembly and said moveable handle portion,

(H) a further smaller longitudinal bore extending through said sleeve assembly,

(I) an elongated transverse slot extending through said sleeve assembly and intersecting said further longitudinal bore,

(J) a pair of toothed jaw members in said transverse slot and moveable radially and longitudinally therein,

(K) said jaw members extending outwardly from said slot into said first longitudinal bore,

(L) said compression spring being disposed to also exert force against those portions of the jaw members 7 extending outwardly from the transverse slot to maintain the jaw members in engagement with the tapered restriction of said first longitudinal bore,

(M) said jaw members being moveable in said transverse slot radially inwardly into the path of said further longitudinal bore, to grasp a rivet mandrel inserted therein, upon forceful engagement of the extending portions of the jaw members with the tapered restriction of said first bore upon movement of the sleeve assembly therein against pressure of said compression spring upon movement of said moveable handle portion, and

(N) said jaw members being each provided with an external flange along the edge opposite from its toothed portion, said flange being wider than said transverse slot and effective to control inward movement of said jaw members and maintain alignment of the jaw members in said slot.

References Cited by the Examiner UNITED STATES PATENTS 2,471,598 5/1949 Wilt 72-391 3,002,644 10/1961 Meyer 7239l 3,003,657 10/1961 Siebel 72391 3,095,106 6/1963 Morrison 72-391 CHARLES W. LANHAM, Primary Examiner.

G. P. CROSBY, Assistant Examiner. 

1. RIVET GUN OF THE CLASS DESCRIBED COMPRISING A FRAME HAVING A STATIONARY PALM ENGAGING HANDLE PORTION, A FINGER ENGAGING HANDLE PORTION PIVOTALLY ATTACHED TO SAID FRAME, SAID GUN HAVING A RELATIVELY SHORT HEAD PORTION, A LONGITUDINALLY BORE EXTENDING THROUGH SAID HEAD PORTION AND HAVING A RESTRICTION ADJACENT THE MUZZLE END THEREOF, A SLEEVE ASSEMBLY DISPOSED WITHIN SAID BORE FOR LIMITED MOVEMENT THEREIN, A LONGITUDINAL BORE EXTENDING THROUGH SAID SLEEVE ASSEMBLY AT LEAST ONE TRANSVERSE SLOT INTERSECTING SAID LONGITUDINAL BORE IN SAID SLEEVE ASSEMBLY, AT LEAST TWO TOOTHED JAW MEMBERS IN SAID TRANSVERSE SLOT, SAID JAW MEMBERS BEING MOVEABLE IN SAID SLOT INTO THE PATH OF THE LONGITUDINAL BORE THROUGH THE SLEEVE ASSEMBLY UPON ENGAGEMENT OF THE JAW MEMBERS WITH THE RESTRICTION OF THE LONGITUDINAL BORE THROUGH THE HEAD PORTION OF THE GUN UPON MOVEMENT OF THE SLEEVE ASSEMBLY, THEREIN UPON MOVEMENT OF SAID FINGER ENGAGING HANDLE PORTION, SAID JAW MEMBERS BEING EACH PROVIDED WITH AN EXTERNAL FLANGE ALONG THE EDGE OPPOSITE FROM ITS TOOTHED PORTION, SAID FLANGE BEING WIDER THAN SAID TRANSVERSE SLOT 